El Niño risk rising for late summer, climate models show

Improving moisture conditions in the southwestern U.S. has improved the outlook for many farms and ranches for 2012, and meteorologists say the La Niña weather pattern responsible for last year’s drought is unlikely to return this year. Farmers on the other side of the globe, however, are rightfully worried about the looming threat of El Niño and the possibilities of drought it may bring to their crops.

Regions of Southeast Asia and Australia are most likely to be affected by an El Niño, and Australia’s Bureau of Meteorology says climate models indicate a possible return of El Niño in the second half of 2012. The last severe El Niño in 1998 killed more than 2,000 people and caused billions of dollars in damage to crops, infrastructure and mines in Australia and other parts of Asia.

According to a Reuters article this week, Australia’s Bureau of Meteorology tracks seven climate models from compatriot meteorology centers around the world, of which five indicate above El Niño conditions, while the remaining two sit on the neutral – neither El Niño or La Niña.

“Nobody is going to say that the models are 100 percent accurate, but if you look at the climate models, the risk of El Niño has gone up in recent weeks,” Andrew Watkins, manager of climate prediction at the Australian Bureau of Meteorology told Reuters.

The World Meteorological Organization maintains its neutral outlook for the second half of the year, but the chief of India’s state-run weather office said El Niño conditions were likely to emerge over the Pacific Ocean by mid-August.

"This (El Niño) may have some bearing on monsoon rains in some pockets of the country (India) in the latter half of the season," L.S. Rathore, director general of the India Meteorological Department, told reporters in New Delhi this week.

El Niño is a warming of ocean surface temperatures in the eastern and central Pacific, the opposite of La Niña. The El Nino phenomena occurs every three to seven years, and strong El Ninos can lead to dramatic weakening of the trade winds that blow west across the Pacific, triggering drought in southeast Asia and Australia and parts of Africa.

El Nino can also cause stormy weather in the southern and western United States. El Ninos also tend to cut the number of Atlantic hurricanes but boost the number of storms in the eastern Pacific. The last El Nino was recorded in 2009-2010, though it was classified as weak to moderate.

The National Oceanic Atmospheric Administration’s seasonal forecast for the U.S. calls for warmer-than-normal temperatures for about three-quarters of the nation. The warmer temperatures are expected south of a line from New Jersey to southern Idaho.

The U.S. just finished recording the hottest 12-month period on record from May 2011 to April 2012, with records dating back to 1895. This year has produced the hottest March, the third warmest April and the fourth warmest January and February in U.S. weather history.